1. Field of the Invention
The present invention relates to an apparatus and method for displaying available service time in mobile telephones, and more particularly to a method of displaying available service time in mobile telephones in terms of a numerical value.
2. Description of the Related Art
In general, mobile telephones or mobile terminals display the charging state of a battery by using an icon, represented in three or four degrees to inform users of the present charging state of the battery. As a standby time of the battery and available service time of the mobile telephones are extended along with development of related technologies, a fully charged battery now enables users to carry the mobile telephones for a few days without the need for recharging. For this reason, users are able to use the mobile telephones even when the power level is low, as shown by an icon on the display being at a first degree or so. However, after users have identified the power level or charging state as being at the first degree or so and have gone out without recharging the battery, they often are made aware of trouble due to an alarm signal indicative of the exhaustion of the battery, which may be followed by a sudden power-off of the mobile terminals (telephones) while in the middle of a call. Although there is some difference between mobile terminals, most mobile terminals can provide a continuous call service for only about 5 minutes or so after the generation of the alarm signal indicative of the exhaustion the battery.
FIG. 1 is a control flowchart illustrating the process for displaying a available service time in mobile telephones according to the prior art.
Referring to FIG. 1, at step 110, when a mobile terminal is powered on, the program proceeds to step 120 in which a controller checks whether or not a currently measured charging level value X of the battery is greater than a power-down threshold value A. If it is determined at step 120 that the currently measured charging level value of the battery X is not greater than the power-down threshold value A, the program proceeds to step 140 where the mobile telephone is powered off. On the other hand, if it is determined at step 120 where the currently measured charging level value X of the battery is greater than the power-down threshold value A, the program proceeds to step 130 where a display section displays an icon according to a degree (B, C, D, or F) corresponding to the currently measured charging level value X of the battery.
The degrees represent battery-charging levels pre-determined numerically according to the type and capacity of the battery. The degree B indicates the third degree (fully charged) level, the degree C indicates the second degree level, the degree D indicates the first degree level, and the degree F indicates a low battery-charging level.
After such an icon has been displayed at step 130, the mobile terminal goes in an idle state.
However, the accuracy of the displayed icon for mobile telephones having batteries with large capacities, such as standby times of six nights and seven days, or as many as sixteen nights and seventeen days, is not well represented by using an icon having only three or four degrees. That is, it is necessary that user be informed of information on how long he is able to use the mobile terminal under the current charging state of the battery, i.e., a concrete and correct indication of serviceable time of the mobile terminal.
Therefore, an object of the present invention is to provide a device for and a method of displaying available service time in mobile telephones in which users can be informed about the charging state of a battery, presented as information expressed numerically and adaptive for variations in performance of the battery according to its use.
In order to achieve the above object, according to one aspect of the present invention, there is provided a device for displaying available service time in a mobile telephone, comprising:
a battery voltage detecting section adapted to measure a current charging level value of a battery when the mobile telephone is powered on;
an analog/digital converter adapted to convert the measured analog current charging level value into a digital value;
a reference data memory adapted to store a predetermined power-down threshold level value depending on the type of each battery;
an available service time-per-unit level memory adapted to store a available service time value per a unit level measured and updated, except an initial default value, any time a user attempts to use the telephone;
an available service time calculating section adapted to calculate a available service time by using both the power-down threshold level value according to a corresponding battery type and the available service time value per the unit level read out from the available service time-per-unit level memory;
an available service time memory adapted to store the calculated available service time therein; and
a display section adapted to display the calculated available service time stored in the available service time memory to inform the user of the current charging state of the battery.
According to another aspect of the present invention, there is provided a method of displaying available service time in a mobile telephone, comprising:
(a) determining whether or not a currently measured charging level value X of a battery is greater than a power-down threshold level value when the mobile telephone is powered on;
(b) displaying an icon corresponding to the currently measured charging level value X of the battery, the icon having a plurality of degrees, if it is determined that the currently measured charging level value X of the battery is greater than the power-down threshold level value;
(c) updating an available service time value Y per a unit level and storing it in a available service time-per-unit level memory upon sensing completion of a call if the mobile telephone is being used; and
(d) reading the available service time value Y per the unit level from the available service time-per-unit level memory, and then calculating a available service time by using the read available service time value Y per the unit level when the selection of a available service time menu is sensed if the mobile telephone is in an idle state after the step (b) has been performed.